For my personal speculation, I think they will reveal there own "Nintendo Switch type of device" that the only thing that can effect Nintendo at this moment. What do you guys think?
Probably another feeble stab at "virtual reality". Although usually when Nintendo pioneers some new sort of technology, the others mimic that technology within 14 months.
There's no way that Sony will release another portable after the Vita - especially with the success of the Switch the competition would be too great. They also won't be announcing a ps5 anytime soon due to the Pro and X. This will mainly be software and reductions in price for consoles and VR.